[ExI] Many Worlds (was: A Simulation Argument)

[Stathis Papaioannou]

On 09/01/2008, Damien Broderick <thespike at satx.rr.com> wrote:

> I have read Deutsch's book with its peculiar talk of shadow photons,
> which appear to subsist in numerous orthogonal universes that
> mysteriously influence each other. And yet most discussions of MWI as
> applied to decisive choices, for example, appear to suppose that any
> observed state branches into a multitude of alternative experiences.
> You turn right, and you turn left, and you go home, and very very
> rarely you fly into the sky. Presumably, therefore, we must imagine
> that in one universe a given light beam will jig along a random dog's
> leg path, and it's only a sort of "God's eye view" that might
> perceive the kind of hyperreality where all those dogs' legs congeal
> into a straight line.
>
> But actually there is no "God's eye view" unless it is the one we
> experience routinely.

The way I understand Deutsch, normally you don't see the superposition
of worlds, but just the world that you're in. Under special
circumstances you can see the effects of the different worlds
interfering with each other but this is a delicate matter and is
disrupted when macroscopic interactions occur: the process of
decoherence, causing an apparent "collapse" of the wavefunction.

A "God's eye view" of the multiverse would show that every possibility
happens. But if you are an observer embedded in this ever-branching
story, able to experience only one branch at a time, it appears that
there is only one linear reality. This also allows for the possibility
of true randomness from a first person perspective while the objective
reality is completely deterministic, since all versions of you are
equivalent but you will only experience one of them as "real".



-- 
Stathis Papaioannou